Monday, August 4, 2014

Welcome to the thirty-first issue of LLVM Weekly, a weekly newsletter
(published every Monday) covering developments in LLVM, Clang, and related
projects. LLVM Weekly is brought to you by Alex
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On the mailing lists

Johannes Kapfhammer, a Google Summer of Code student has posted an RFC on
adding a fuzzy parser for highlighting
C++. The
Clang parser can't be used for this as it may be highlighting incomplete
snippets where not all types or functions are included. It was pointed out in
responses that this is similar to clang-format's parser, but apparently this
parser is not easily reusable and very tied to the clang-format
implementation.

In response to a question about documentation for adding builders to the
LLVM buildbot service, Dan Liew has posted a summary of how he has done
it. He's
looking for feedback on whether this is the best way to do things.

Tom Stellard proposes renaming the R600 target to
AMDGPU. The
motivation is that the backend has the name since the R600 was the first AMD
GPU targeted, but it has added support for all AMD GPUs since then. There
seems to be agreement this would be a sensible renaming.

LLVM commits

FastISel for AArch64 saw a number of improvements, including support for
shift-immediate, arithmetic with overflow intrinsics.
r214345,
r214348, and more.

The SLPVectorizer has seen a largeish commit that implements an "improved
scheduling algorithm". Sadly the commit message offers no further details.
r214494.

TargetInstrInfo gained isAsCheapAsMove which takes a MachineInstruction
and returns true if that instruction is as cheap as a move instruction.
r214158.

LLVM libraries can now be exported as importable CMake targets, making it
easier for those building LLVM-based projects. This is now documented.
r214077.

Release notes for PowerPC changes during 3.5 development have been
committed. r214403.